The present disclosure relates to an image sensor and a method for manufacturing the same.
Generally, image sensors are semiconductor devices which can convert optical images into electrical signals. Such image sensors can typically be classified as either charge coupled device (CCD) image sensors or complementary metal oxide semiconductor (CMOS) image sensors.
CMOS image sensors include photodiodes and MOS transistors in unit pixels that detect electrical signals in the respective unit pixels in a switching mode, thereby realizing an image.
A related art process for manufacturing a CMOS image sensor includes deposition and chemical-mechanical polishing processes for forming multi-layers including a plurality of metal lines and insulating layers after the forming of a photodiode on a substrate.
This causes an increase in the number of bad pixels due to reduction of photosensitivity and increased number of defects, which are caused by the increase of an interval distance from a photodiode to a color filter or microlens due to the multi-layers.